Discarded kidneys could be `recycled` to produce replacement organs

Washington: Researchers have found that human kidneys discarded for transplant can potentially serve as a natural "scaffolding material" for manufacturing replacement organs in the lab using regenerative medicine techniques.

According to the researchers at Wake Forest Baptist Medical Center and colleagues, more than 2,600 donor kidneys are discarded each year in the US.

"With about 100,000 people in the US awaiting kidney transplants, it is devastating when an organ is donated but cannot be used. These discarded organs may represent an ideal platform for investigations aimed at manufacturing kidneys for transplant," said Giuseppe Orlando, M.D., Ph.D., lead author, a Wake Forest Baptist transplant surgeon and regenerative medicine researcher.

The research involved pumping a mild detergent through kidneys that were refused for transplant. The goal of the process, called decellularization, is to remove all cells - leaving only the organ structure or "skeleton," known in regenerative medicine terms as a scaffold. Ultimately, the patient`s own cells could be placed in this scaffold, creating a customized organ that the patient theoretically would not reject.

In fact, an analysis of the decellularized organs revealed that antigens likely to cause an immune response were removed in the cleaning process.

"This finding has significant implications. It indicates that transplantation of such customized kidneys could be performed without the need for anti-rejection therapy. In addition, these kidneys maintain their innate three-dimensional architecture, their basic biochemistry, as well as their vessel network system. When we tested their ability to be transplanted (in pigs), these kidneys were able to maintain blood pressure, suggesting a functional and resilient vasculature," said Orlando.

While the project is in its infancy, the idea represents a potential solution to the extreme shortage of donor kidneys.

The research, supported in part by a grant from the state of North Carolina, was reported in the journal Biomaterials.